Publications by authors named "Yu-Wei Lee"

28 Publications

  • Page 1 of 1

Detecting Effects of Low Levels of FCCP on Stem Cell Micromotion and Wound-Healing Migration by Time-Series Capacitance Measurement.

Sensors (Basel) 2021 Apr 25;21(9). Epub 2021 Apr 25.

Department of Biomedical Engineering, National Yang-Ming University, Taipei 11221, Taiwan.

Electric cell-substrate impedance sensing (ECIS) has been used as a real-time impedance-based method to quantify cell behavior in tissue culture. The method is capable of measuring both the resistance and capacitance of a cell-covered microelectrode at various AC frequencies. In this study, we demonstrate the application of high-frequency capacitance measurement (f = 40 or 64 kHz) for the sensitive detection of both the micromotion and wound-healing migration of human mesenchymal stem cells (hMSCs). Impedance measurements of cell-covered electrodes upon the challenge of various concentrations of carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone (FCCP), from 0.1 to 30 μM, were conducted using ECIS. FCCP is an uncoupler of mitochondrial oxidative phosphorylation (OXPHOS), thereby reducing mitochondrial ATP production. By numerically analyzing the time-series capacitance data, a dose-dependent decrease in hMSC micromotion and wound-healing migration was observed, and the effect was significantly detected at levels as low as 0.1 μM. While most reported works with ECIS use the resistance/impedance time series, our results suggest the potential use of high-frequency capacitance time series for assessing migratory cell behavior such as micromotion and wound-healing migration.
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http://dx.doi.org/10.3390/s21093017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8123359PMC
April 2021

A Rapid and Highly Predictive Screening Platform for Osteogenic Natural Compounds Using Human Runx2 Transcriptional Activity in Mesenchymal Stem Cells.

Front Cell Dev Biol 2020 8;8:607383. Epub 2021 Jan 8.

Department of Obstetrics and Gynecology, National Taiwan University (NTU) Hospital and College of Medicine, Taipei, Taiwan.

The rapid aging of worldwide populations had led to epidemic increases in the incidence of osteoporosis (OP), but while treatments are available, high cost, adverse effects, and poor compliance continue to be significant problems. Naturally occurring plant-based compounds including phytoestrogens can be good and safe candidates to treat OP, but screening for osteogenic capacity has been difficult to achieve, largely due to the requirement of using primary osteoblasts or mesenchymal stem cells (MSCs), the progenitors of osteoblasts, to conduct time-consuming and osteogenic assay. Taking advantage of MSC osteogenic capacity and utilizing a promoter reporter assay for Runx2, the master osteogenesis transcription factor, we developed a rapid screening platform to screen osteogenic small molecules including natural plant-based compounds. We screened eight plant-derived compounds from different families including flavonoids, polyphenolic compounds, alkaloids, and isothiocyanates for osteogenic capacity using the human RUNX2-promoter luciferase reporter (hRUNX2-luc) transduced into the mouse MSC line, C3H10T1/2, with daidzein-a well-studied osteogenic phytoestrogen-as a positive control. Classical and osteogenesis assays were performed using primary murine and human bone marrow MSCs (BMMSCs) to validate the accuracy of this rapid screening platform. Using the MSC/hRUNX2-luc screening platform, we were able not only to shorten the selection process for osteogenic compounds from 3∼4 weeks to just a few days but also simultaneously perform comparisons between multiple compounds to assess relative osteogenic potency. Predictive analyses revealed nearly absolute correlation of the MSC/hRUNX2-luc reporter platform to the classical functional assay of mineralization using murine BMMSCs. Validation using human BMMSCs with mineralization and osteogenesis assays also demonstrated nearly absolute correlation to the MSC/hRUNX2-luc reporter results. Our findings therefore demonstrate that the MSC/hRUNX2 reporter platform can accurately, rapidly, and robustly screen for candidate osteogenic compounds and thus be relevant for therapeutic application in OP.
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http://dx.doi.org/10.3389/fcell.2020.607383DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7849832PMC
January 2021

Resident vs nonresident multipotent mesenchymal stromal cell interactions with B lymphocytes result in disparate outcomes.

Stem Cells Transl Med 2021 May 28;10(5):711-724. Epub 2021 Jan 28.

Regenerative Medicine Research Group, Institute of Cellular and System Medicine, National Health Research Institutes (NHRI), Zhunan, Taiwan.

Multipotent human mesenchymal stromal cells (MSCs) from multiple organs including the bone marrow (BM) and placenta harbor clinically relevant immunomodulation best demonstrated toward T lymphocytes. Surprisingly, there is limited knowledge on interactions with B lymphocytes, which originate from the BM where there is a resident MSC. With increasing data demonstrating MSC tissue-specific propensities impacting therapeutic outcome, we therefore investigated the interactions of BM-MSCs-its resident and "niche" MSC-and placental MSCs (P-MSCs), another source of MSCs with well-characterized immunomodulatory properties, on the global functional outcomes of pan-peripheral B cell populations. We found that P-MSCs but not BM-MSCs significantly inhibit proliferation and further differentiation of stimulated human peripheral B populations in vitro. Moreover, although BM-MSCs preserve multiple IL-10-producing regulatory B cell (Breg) subsets, P-MSCs significantly increase all subsets. To corroborate these in vitro findings in vivo, we used a mouse model of B-cell activation and found that adoptive transfer of P-MSCs but not BM-MSCs significantly decreased activated B220 B cells. Moreover, adoptive transfer of P-MSCs but not BM-MSCs significantly decreased the overall B220 B-cell proliferation and further differentiation, similar to the in vitro findings. P-MSCs also increased two populations of IL-10-producing murine Bregs more strongly than BM-MSCs. Transcriptome analyses demonstrated multifactorial differences between BM- and P-MSCs in the profile of relevant factors involved in B lymphocyte proliferation and differentiation. Our results highlight the divergent outcomes of tissue-specific MSCs interactions with peripheral B cells, and demonstrate the importance of understanding tissue-specific differences to achieve more efficacious outcome with MSC therapy.
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http://dx.doi.org/10.1002/sctm.20-0289DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8046079PMC
May 2021

Development and implementation of guidelines for the management of depression: a systematic review.

Bull World Health Organ 2020 Oct 27;98(10):683-697H. Epub 2020 Aug 27.

School of Clinical Medicine, The University of Queensland, Brisbane, Australia.

Objective: To evaluate the development and implementation of clinical practice guidelines for the management of depression globally.

Methods: We conducted a systematic review of existing guidelines for the management of depression in adults with major depressive or bipolar disorder. For each identified guideline, we assessed compliance with measures of guideline development quality (such as transparency in guideline development processes and funding, multidisciplinary author group composition, systematic review of comparative efficacy research) and implementation (such as quality indicators). We compared guidelines from low- and middle-income countries with those from high-income countries.

Findings: We identified 82 national and 13 international clinical practice guidelines from 83 countries in 27 languages. Guideline development processes and funding sources were explicitly specified in a smaller proportion of guidelines from low- and middle-income countries (8/29; 28%) relative to high-income countries (35/58; 60%). Fewer guidelines (2/29; 7%) from low- and middle-income countries, relative to high-income countries (22/58; 38%), were authored by a multidisciplinary development group. A systematic review of comparative effectiveness was conducted in 31% (9/29) of low- and middle-income country guidelines versus 71% (41/58) of high-income country guidelines. Only 10% (3/29) of low- and middle-income country and 19% (11/58) of high-income country guidelines described plans to assess quality indicators or recommendation adherence.

Conclusion: Globally, guideline implementation is inadequately planned, reported and measured. Narrowing disparities in the development and implementation of guidelines in low- and middle-income countries is a priority. Future guidelines should present strategies to implement recommendations and measure feasibility, cost-effectiveness and impact on health outcomes.
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http://dx.doi.org/10.2471/BLT.20.251405DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7652558PMC
October 2020

Inter-relationships between burnout, personality and coping features in residents within an ACGME-I Accredited Psychiatry Residency Program.

Asia Pac Psychiatry 2020 Aug 19:e12413. Epub 2020 Aug 19.

Department of Mood and Anxiety, West Region, Institute of Mental Health, Singapore, Singapore.

Background: Burnout during residency training is associated with various factors. Within the context of stress/coping transactional model in which one's personality can influence stress appraisal and coping, there is limited evidence examining the relationship between burnout and personality factors amongst psychiatry residents.

Objectives: We aim to evaluate the prevalence of burnout within a cohort of psychiatry residents and its relationship with personality factors, demographic, work-related factors and coping features.

Methods: We conducted a cross-sectional study involving 50 out of 77 eligible residents (response rate 64.9%) and administered the Oldenberg Burnout Inventory (OLBI), NEO-Five Factor Inventory (NEO-FFI) and Brief COPE Inventory. Burnout was defined as crossing the thresholds for exhaustion (≥2.25) and disengagement (≥2.1) scores. We compared the burnout vs nonburnout groups and examined the relationship between burnout, personality factors and coping strategies using correlational and mediational analyses.

Results: Overall, 78% of our cohort met criteria for burnout. Burnout was correlated with hours of work per week (rs = .409, P = .008), neuroticism (OR 1.2, 95% CI 1.01-1.43, P = .041) and avoidance coping (OR 1.61, 95% CI 1.06-2.46, P = .025). Neuroticism was significantly correlated (all P < .001) with all coping domains (Seeking Social Support, rs = 0.40; Problem Solving, rs = 0.52; Avoidance, rs = 0.55; Positive thinking, rs = 0.41) and was a partial mediator between avoidance coping and burnout (β of indirect path = 0.168, [SE = 0.066]; P = .011).

Conclusions: We found a considerable burnout rate amongst psychiatry residents which was associated with neuroticism and avoidance coping, and suggest ways to better tackle occupational burnout during residency training.
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http://dx.doi.org/10.1111/appy.12413DOI Listing
August 2020

Selection of New Psychiatry Residents Within a National Program: a Qualitative Study of Faculty Perspectives on Competencies and Attributes.

Acad Psychiatry 2020 Oct 23;44(5):545-553. Epub 2020 Jul 23.

National Healthcare Group, Singapore, Singapore.

Objective: Admission committees use multiple sources of information to select residents. However, the way in which faculty members use each data source remains unclear and highly context-specific. The present study seeks to understand how faculty members use various sources of information about candidates to make admission decisions to a National Psychiatry Residency Program.

Methods: The theory of core competencies was used as a foundation for this qualitative study. Framework analysis was used to structure the project and data presentation. Twenty key informants from the faculty were purposefully sampled in accordance with the initial theory. Open-ended semi-structured interviews were conducted to obtain their views about the essential competencies of psychiatrists and the ways in which these competencies could be reliably gauged.

Results: Participants described numerous competencies that they believed were essential to becoming competent psychiatrists. These competencies fell within the six core competencies of the Accreditation Council for Graduate Medical Education framework. However, several non-competency attributes (such as perseverance, empathy, and compassion) were also relevant in the selection process. To reduce the impact of self-presentation bias, to which these attributes were vulnerable, the faculty relied heavily on sources of information obtained from third parties, such as feedback from co-workers with first-hand experience of the candidate during their clinical placements.

Conclusion: Faculty members place importance on informal informant-derived information about a candidate's non-competency attributes in addition to core competencies when deciding whether or not to select a candidate for admission into a residency training program.
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http://dx.doi.org/10.1007/s40596-020-01282-1DOI Listing
October 2020

COVID-19, a pandemic that affects more than just physical health: Two case reports.

Asian J Psychiatr 2020 Oct 9;53:102200. Epub 2020 Jun 9.

Department of Mood and Anxiety, Institute of Mental Health, Singapore.

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http://dx.doi.org/10.1016/j.ajp.2020.102200DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7282747PMC
October 2020

Application of ECIS to Assess FCCP-Induced Changes of MSC Micromotion and Wound Healing Migration.

Sensors (Basel) 2019 Jul 21;19(14). Epub 2019 Jul 21.

Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan.

Electric cell-substrate impedance sensing (ECIS) is an emerging technique for sensitively monitoring morphological changes of adherent cells in tissue culture. In this study, human mesenchymal stem cells (hMSCs) were exposed to different concentrations of carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone (FCCP) for 20 h and their subsequent concentration-dependent responses in micromotion and wound healing migration were measured by ECIS. FCCP disrupts ATP synthesis and results in a decrease in cell migration rates. To detect the change of cell micromotion in response to FCCP challenge, time-series resistances of cell-covered electrodes were monitored and the values of variance were calculated to verify the difference. While Seahorse XF-24 extracellular flux analyzer can detect the effect of FCCP at 3 μM concentration, the variance calculation of the time-series resistances measured at 4 kHz can detect the effect of FCCP at concentrations as low as 1 μM. For wound healing migration, the recovery resistance curves were fitted by sigmoid curve and the hill slope showed a concentration-dependent decline from 0.3 μM to 3 μM, indicating a decrease in cell migration rate. Moreover, dose dependent incline of the inflection points from 0.3 μM to 3 μM FCCP implied the increase of the half time for wound recovery migration. Together, our results demonstrate that partial uncoupling of mitochondrial oxidative phosphorylation reduces micromotion and wound healing migration of hMSCs. The ECIS method used in this study offers a simple and sensitive approach to investigate stem cell migration and its regulation by mitochondrial dynamics.
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http://dx.doi.org/10.3390/s19143210DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6679573PMC
July 2019

Combining CRISPR/Cas9-mediated knockout with genetic complementation for in-depth mechanistic studies in human ES cells.

Biotechniques 2019 01;66(1):23-27

Department of Genetics and Yale Stem Cell Center, Yale University, New Haven, CT, USA.

Gene regulatory networks that control pluripotency of human embryonic stem cells (hESCs) are of considerable interest for regenerative medicine. RNAi and CRISPR/Cas9 technologies have allowed the identification of hESC regulators on a genome-wide scale. However, these technologies are ill-suited for mechanistic studies because knockdown/knockout clones of essential genes do not grow in culture. We have developed a genetic rescue strategy that combines CRISPR/Cas9-mediated knockout with TALEN-mediated integration of a doxycycline-inducible rescue transgene into a constitutive AASV1 locus. The resulting rescue clones are stable in culture, allow modulation of the rescue transgene dosage by titration of doxycycline in the media and can be combined with various molecular assays, thus providing mechanistic insights into gene function in a variety of cellular contexts.
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http://dx.doi.org/10.2144/btn-2018-0115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7408315PMC
January 2019

Wharton' jelly mesenchymal stromal cell therapy for ischemic brain injury.

Brain Circ 2018 Jul-Sep;4(3):124-127. Epub 2018 Oct 9.

Center for Neuropsychiatric Research, National Health Research Institutes, Miaoli County, Taiwan.

Increasing evidence have supported that Wharton's jelly mesenchymal stem cell (WJ-MSCs) have immunomodulatory and protective effects against several diseases including kidney, liver pathologies, and heart injury. Few studies have reported that WJ-MSCs reduced inflammation in hippocampal slices after oxygen-glucose deprivation. We recently reported the neuroprotective effects of human WJ-MSCs (hWJ-MSCs) in rats exposed to a transient right middle cerebral artery occlusion. hWJ-MSCs transplantation significantly reduced brain infarction and microglia activation in the penumbra leading with a significant reduction of neurological deficits. Interestingly, the grafted hWJ-MSCs in the ischemic core were mostly incorporated into IBA1 (+) cells, suggesting that hWJ-MSCs were immunorejected by the host. The immune rejection of hWJ-MSCs was reduced in after cyclosporine A treatment. Moreover, the glia cell line-derived neurotrophic factor expression was significantly increased in the host brain after hWJ-MSCs transplantation. In conclusion, these results suggest that the protective effect of hWJ-MSCs may be due to the secretion of trophic factors rather than to the survival of grafted cells. This paper is a review article. Referred literature in this paper has been listed in the references section. The data sets supporting the conclusions of this article are available online by searching various databases, including PubMed. Some original points in this article come from the laboratory practice in our research center and the authors' experiences.
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http://dx.doi.org/10.4103/bc.bc_16_18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6187942PMC
October 2018

Neuroprotective Action of Human Wharton's Jelly-Derived Mesenchymal Stromal Cell Transplants in a Rodent Model of Stroke.

Cell Transplant 2018 Nov 4;27(11):1603-1612. Epub 2018 Oct 4.

Center for Neuropsychiatric Research, National Health Research Institutes (NHRI), Miaoli, Taiwan.

Wharton's jelly-derived mesenchymal stromal cells (WJ-MSCs) have distinct immunomodulatory and protective effects against kidney, liver, or heart injury. Limited studies have shown that WJ-MSCs attenuates oxygen-glucose deprivation-mediated inflammation in hippocampal slices. The neuroprotective effect of intracerebral WJ-MSC transplantation against stroke has not been well characterized. The purpose of this study was to examine the neuroprotective effect of human WJ-MSC (hWJ-MSC) transplants in an animal model of stroke. Adult male Sprague-Dawley rats were anesthetized and placed in a stereotaxic frame. hWJ-MSCs, pre-labeled with chloromethyl benzamide 1,1'-dioctadecyl-3,3,3'3'- tetramethylindocarbocyanine perchlorate (CM-Dil), were transplanted to the right cerebral cortex at 10 min before a transient (60 min) right middle cerebral artery occlusion (MCAo). Transplantation of hWJ-MSCs significantly reduced neurological deficits at 3 and 5 days after MCAo. hWJ-MSC transplants also significantly reduced brain infarction and microglia activation in the penumbra. Grafted cells carrying CM-Dil fluorescence were identified at the grafted site in the ischemic core; these cells were mostly incorporated into ionized calcium-binding adaptor molecule (+) cells, suggesting these xenograft cells were immuno-rejected by the host. In another set of animals, hWJ-MSCs were transplanted in cyclosporine (CsA)-treated rats. hWJ-MSC transplants significantly reduced brain infarction, improved neurological function, and reduced neuroinflammation. Less phagocytosis of CM-dil-labeled grafted cells was found in the host brain after CsA treatment. Transplantation of hWJ-MSC significantly increased glia cell line-derived neurotrophic factor expression in the host brain. Taken together, our data support that intracerebral transplantation of hWJ-MSCs reduced neurodegeneration and inflammation in the stroke brain. The protective effect did not depend on the survival of grafted cells but may be indirectly mediated through the production of protective trophic factors from the transplants.
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http://dx.doi.org/10.1177/0963689718802754DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6299196PMC
November 2018

Dppa2/4 Facilitate Epigenetic Remodeling during Reprogramming to Pluripotency.

Cell Stem Cell 2018 09 23;23(3):396-411.e8. Epub 2018 Aug 23.

Department of Genetics, Yale University, New Haven, CT, USA; Yale Stem Cell Center, Yale University, New Haven, CT, USA. Electronic address:

As somatic cells are converted into induced pluripotent stem cells (iPSCs), their chromatin is remodeled to a pluripotent configuration with unique euchromatin-to-heterochromatin ratios, DNA methylation patterns, and enhancer and promoter status. The molecular machinery underlying this process is largely unknown. Here, we show that embryonic stem cell (ESC)-specific factors Dppa2 and Dppa4 play a key role in resetting the epigenome to a pluripotent state. They are induced in reprogramming intermediates, function as a heterodimer, and are required for efficient reprogramming of mouse and human cells. When co-expressed with Oct4, Klf4, Sox2, and Myc (OKSM) factors, Dppa2/4 yield reprogramming efficiencies that exceed 80% and accelerate reprogramming kinetics, generating iPSCs in 2 to 4 days. When bound to chromatin, Dppa2/4 initiate global chromatin decompaction via the DNA damage response pathway and contribute to downregulation of somatic genes and activation of ESC enhancers, all of which enables an efficient transition to pluripotency. Our work provides critical insights into how the epigenome is remodeled during acquisition of pluripotency.
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http://dx.doi.org/10.1016/j.stem.2018.08.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6128737PMC
September 2018

Novel mutations in Chinese Han patients with tuberous sclerosis complex: Case series and review of the published work.

J Dermatol 2018 Jul 9;45(7):867-870. Epub 2018 May 9.

Institute of Dermatology and Department of Dermatology of First Affiliated Hospital, Hefei, China.

Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disease characterized by hamartomas in multiple organ systems. This study was performed in one familial and two sporadic cases with TSC. Two novel mutations (c.1884_1887delAAAG and c.5266A>G) and two previously reported mutations (c.4258_4261delTCAG and c.1960G>C) were identified by direct DNA sequencing. Of the four mutations, c.1884_1887delAAAG and c.1960G>C were found in a family and identified in the same allele by TA cloning sequencing. However, c.1960G>C was reported to be non-pathogenic. Furthermore, correlations between genotypes and phenotypes of Chinese Han patients since 2014 were performed by paired χ -tests in our published work review, which has not been reported. The results showed that patients with TSC2 mutations had a higher frequency of mental retardation and there were no significant differences of seizures and skin lesions with TSC1 mutations. Genetically, they had a higher frequency of familial inheritance.
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http://dx.doi.org/10.1111/1346-8138.14349DOI Listing
July 2018

A Non-canonical BCOR-PRC1.1 Complex Represses Differentiation Programs in Human ESCs.

Cell Stem Cell 2018 02 11;22(2):235-251.e9. Epub 2018 Jan 11.

Department of Genetics, Yale University, New Haven, CT 06520, USA; Yale Stem Cell Center, Yale University, New Haven, CT 06520, USA. Electronic address:

Polycomb group proteins regulate self-renewal and differentiation in many stem cell systems. When assembled into two canonical complexes, PRC1 and PRC2, they sequentially deposit H3K27me3 and H2AK119ub histone marks and establish repressive chromatin, referred to as Polycomb domains. Non-canonical PRC1 complexes retain RING1/RNF2 E3-ubiquitin ligases but have unique sets of accessory subunits. How these non-canonical complexes recognize and regulate their gene targets remains poorly understood. Here, we show that the BCL6 co-repressor (BCOR), a member of the PRC1.1 complex, is critical for maintaining primed pluripotency in human embryonic stem cells (ESCs). BCOR depletion leads to the erosion of Polycomb domains at key developmental loci and the initiation of differentiation along endoderm and mesoderm lineages. The C terminus of BCOR regulates the assembly and targeting of the PRC1.1 complex, while the N terminus contributes to BCOR-PRC1.1 repressor function. Our findings advance understanding of Polycomb targeting and repression in ESCs and could apply broadly across developmental systems.
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http://dx.doi.org/10.1016/j.stem.2017.12.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5797497PMC
February 2018

Human pluripotent stem cell (PSC)-derived mesenchymal stem cells (MSCs) show potent neurogenic capacity which is enhanced with cytoskeletal rearrangement.

Oncotarget 2016 Jul;7(28):43949-43959

Regenerative Medicine Research Group, Institute of Cellular and System Medicine, National Health Research Institutes (NHRI), Zhunan, Taiwan.

Mesenchymal stem cells (MSCs) are paraxial mesodermal progenitors with potent immunomodulatory properties. Reports also indicate that MSCs can undergo neural-like differentiation, offering hope for use in neurodegenerative diseases. However, ex vivo expansion of these rare somatic stem cells for clinical use leads to cellular senescence. A newer source of MSCs derived from human pluripotent stem cells (PSC) can offer the 'best-of-both-worlds' scenario, abrogating the concern of teratoma formation while preserving PSC proliferative capacity. PSC-derived MSCs (PSC-MSCs) also represent MSCs at the earliest developmental stage, and we found that these MSCs harbor stronger neuro-differentiation capacity than post-natal MSCs. PSC-MSCs express higher levels of neural stem cell (NSC)-related genes and transcription factors than adult bone marrow MSCs at baseline, and rapidly differentiate into neural-like cells when cultured in either standard neurogenic differentiation medium (NDM) or when the cytoskeletal modulator RhoA kinase (ROCK) is inhibited. Interestingly, when NDM is combined with ROCK inhibition, PSC-MSCs undergo further commitment, acquiring characteristics of post-mitotic neurons including nuclear condensation, extensive dendritic growth, and neuron-restricted marker expression including NeuN, β-III-tubulin and Doublecortin. Our data demonstrates that PSC-MSCs have potent capacity to undergo neural differentiation and also implicate the important role of the cytoskeleton in neural lineage commitment.
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http://dx.doi.org/10.18632/oncotarget.9947DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5190070PMC
July 2016

Coalition of Nuclear Receptors in the Nervous System.

J Cell Physiol 2015 Dec;230(12):2875-80

Hannover Medical School, Department of Neuroanatomy, Hannover, Germany.

A universal signaling module has been described which utilizes the nuclear form of Fibroblast growth Factor Receptor 1 (FGFR1) in a central role directing the post-mitotic development of neural cells through coordinated gene expression. In this review, we discuss in detail the current knowledge of FGFR1 nuclear interaction partners in three scenarios: (i) Engagement of FGFR1 in neuronal stem cells and regulation of neuronal differentiation; (ii) interaction with the orphan receptor Nurr1 in development of mesencephalic dopaminergic neurons; (iii) modulation of nuclear FGFR1 interactions downstream of nerve growth factor (NGF) signaling. These coalitions demonstrate the versatility of non-canonical, nuclear tyrosine kinase signaling in diverse cellular differentiation programs of neurons.
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http://dx.doi.org/10.1002/jcp.25036DOI Listing
December 2015

Global Developmental Gene Programing Involves a Nuclear Form of Fibroblast Growth Factor Receptor-1 (FGFR1).

PLoS One 2015 29;10(4):e0123380. Epub 2015 Apr 29.

Department of Pathology and Anatomical Sciences, Western New York Stem Cell Culture and Analysis Center, State University of New York at Buffalo, Buffalo, New York, United States of America.

Genetic studies have placed the Fgfr1 gene at the top of major ontogenic pathways that enable gastrulation, tissue development and organogenesis. Using genome-wide sequencing and loss and gain of function experiments the present investigation reveals a mechanism that underlies global and direct gene regulation by the nuclear form of FGFR1, ensuring that pluripotent Embryonic Stem Cells differentiate into Neuronal Cells in response to Retinoic Acid. Nuclear FGFR1, both alone and with its partner nuclear receptors RXR and Nur77, targets thousands of active genes and controls the expression of pluripotency, homeobox, neuronal and mesodermal genes. Nuclear FGFR1 targets genes in developmental pathways represented by Wnt/β-catenin, CREB, BMP, the cell cycle and cancer-related TP53 pathway, neuroectodermal and mesodermal programing networks, axonal growth and synaptic plasticity pathways. Nuclear FGFR1 targets the consensus sequences of transcription factors known to engage CREB-binding protein, a common coregulator of transcription and established binding partner of nuclear FGFR1. This investigation reveals the role of nuclear FGFR1 as a global genomic programmer of cell, neural and muscle development.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0123380PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4414453PMC
February 2016

Transplantation of human placenta-derived multipotent stem cells reduces ischemic brain injury in adult rats.

Cell Transplant 2015 9;24(3):459-70. Epub 2015 Feb 9.

Center for Neuropsychiatric Research, National Health Research Institutes (NHRI), Miaoli, Taiwan.

After the onset of stroke, a series of progressive and degenerative reactions, including inflammation, is activated, which leads to cell death. We recently reported that human placenta-derived multipotent stem cells (hPDMCs) process potent anti-inflammatory effects. In this study, we examined the protective effect of hPDMC transplants in a rodent model of stroke. Adult male Sprague-Dawley rats were anesthetized. hPDMCs labeled with a vital dye of fluorescing microparticles, DiI, or vehicle were transplanted into three cortical areas adjacent to the right middle cerebral artery (MCA). Five minutes after grafting, the right MCA was transiently occluded for 60 min. Stroke animals receiving hPDMCs showed a significant behavioral improvement and reduction in lesion volume examined by T2-weighted images 4 days poststroke. Brain tissues were collected 1 day later. Human-specific marker HuNu immunoreactivity and DiI fluorescence were found at the hPDMC graft sites, suggesting the survival of hPDMCs in host brain. Grafting of hPDMCs suppressed IBA1 immunoreactivity and deramification of IBA1(+) cells in the perilesioned area, suggesting activation of microglia was attenuated by the transplants. Taken together, our data indicate that hPDMC transplantation reduced cortical lesions and behavioral deficits in adult stroke rats, and these cells could serve as a unique anti-inflammatory reservoir for the treatment of ischemic brain injury.
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http://dx.doi.org/10.3727/096368915X686922DOI Listing
December 2015

Regulation of neuronal differentiation by proteins associated with nuclear bodies.

PLoS One 2013 17;8(12):e82871. Epub 2013 Dec 17.

Institute of Neuroanatomy, Hannover Medical School, Hannover, Germany ; Center for Systems Neuroscience, University of Veterinary Medicine Hannover, Hannover, Germany.

Nuclear bodies are large sub-nuclear structures composed of RNA and protein molecules. The Survival of Motor Neuron (SMN) protein localizes to Cajal bodies (CBs) and nuclear gems. Diminished cellular concentration of SMN is associated with the neurodegenerative disease Spinal Muscular Atrophy (SMA). How nuclear body architecture and its structural components influence neuronal differentiation remains elusive. In this study, we analyzed the effects of SMN and two of its interaction partners in cellular models of neuronal differentiation. The nuclear 23 kDa isoform of Fibroblast Growth Factor - 2 (FGF-2(23)) is one of these interacting proteins - and was previously observed to influence nuclear bodies by destabilizing nuclear gems and mobilizing SMN from Cajal bodies (CBs). Here we demonstrate that FGF-2(23) blocks SMN-promoted neurite outgrowth, and also show that SMN disrupts FGF-2(23)-dependent transcription. Our results indicate that FGF-2(23) and SMN form an inactive complex that interferes with neuronal differentiation by mutually antagonizing nuclear functions. Coilin is another nuclear SMN binding partner and a marker protein for Cajal bodies (CBs). In addition, coilin is essential for CB function in maturation of small nuclear ribonucleoprotein particles (snRNPs). The role of coilin outside of Cajal bodies and its putative impacts in tissue differentiation are poorly defined. The present study shows that protein levels of nucleoplasmic coilin outside of CBs decrease during neuronal differentiation. Overexpression of coilin has an inhibitory effect on neurite outgrowth. Furthermore, we find that nucleoplasmic coilin inhibits neurite outgrowth independent of SMN binding revealing a new function for coilin in neuronal differentiation.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0082871PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3866168PMC
October 2014

Activation of developmental nuclear fibroblast growth factor receptor 1 signaling and neurogenesis in adult brain by α7 nicotinic receptor agonist.

Stem Cells Transl Med 2013 Oct 6;2(10):776-88. Epub 2013 Sep 6.

Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, New York, USA.

Reactivation of endogenous neurogenesis in the adult brain or spinal cord holds the key for treatment of central nervous system injuries and neurodegenerative disorders, which are major health care issues for the world's aging population. We have previously shown that activation of developmental integrative nuclear fibroblast growth factor receptor 1 (FGFR1) signaling (INFS), via gene transfection, reactivates neurogenesis in the adult brain by promoting neuronal differentiation of brain neural stem/progenitor cells (NS/PCs). In the present study, we report that targeting the α7 nicotinic acetylcholine receptors (α7nAChRs) with a specific TC-7020 agonist led to a robust accumulation of endogenous FGFR1 in the cell nucleus. Nuclear FGFR1 accumulation was accompanied by an inhibition of proliferation of NS/PCs in the subventricular zone (SVZ) and by the generation of new neurons. Neuronal differentiation was observed in different regions of the adult mouse brain, including (a) βIII-Tubulin-expressing cortical neurons, (b) calretinin-expressing hippocampal neurons, and (c) cells in substantia nigra expressing the predopaminergic Nurr1+ phenotype. Furthermore, we showed that in vitro stimulation of neural stem/progenitor cells with α7nAChR agonist directly activated INFS and neuronal-like differentiation. TC-7020 stimulation of the βIII-Tubulin gene was accompanied by increased binding of FGFR1, CREB binding protein, and RNA polymerase II to a Nur77 targeted promoter region. TC-7020 augmented Nur77-dependent activation of nerve growth factor inducible-B protein responsive element, indicating that α7nAChR upregulation of βIII-Tubulin involves neurogenic FGFR1-Nur signaling. The reactivation of INFS and neurogenesis in adult brain by the α7nAChR agonist may offer a new strategy to treat brain injuries, neurodegenerative diseases, and neurodevelopmental diseases.
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http://dx.doi.org/10.5966/sctm.2012-0103DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3785262PMC
October 2013

α7 nicotinic receptor agonist reactivates neurogenesis in adult brain.

Biochem Pharmacol 2013 Oct 9;86(8):1099-104. Epub 2013 Aug 9.

Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, NY, USA.

Reactivation of neurogenesis by endogenous Neural Stem/Progenitor Cells (NS/PC) in the adult brain or spinal cord holds the key for treatment of CNS injuries as well as neurodegenerative disorders, which are major healthcare issues for the world's aging population. Recent studies show that targeting the α7 nicotinic acetylcholine receptors (α7nAChR) with a specific TC-7020 agonist inhibits proliferation and stimulates neuronal differentiation of NS/PC in subventricular zone (SVZ) in the adult mouse brain. TC-7020-induced neuronogenesis is observed in different brain regions, including: (1) βIII Tubulin-expressing cortical neurons, (2) calretinin expressing hippocampal neurons and (3) cells in substantia nigra (SN) expressing predopaminergic Nurr1+phenotype. Reactivation of developmental integrative nuclear FGFR1 signaling (INFS), via gene transfection reinstates neurogenesis in the adult brain by promoting neuronal differentiation of brain NS/PC. TC-7020 neuronogenic effect is associated with a robust accumulation of endogenous FGFR1 in the nuclei of differentiating cells. Furthermore, direct in vitro stimulation of neural stem/progenitor cells with α7nAChR agonist activates INFS and neuronal-like differentiation and activation of neuronal genes. The α7nAChR upregulation of early neuronal βIII-Tubulin gene involves neurogenic FGFR1-Nur signaling and direct FGFR1 interaction with the gene promoter. The reactivation of developmental INFS and neurogenesis in adult brain by the α7nAChR agonist may offer new strategy to treat brain injuries, neurodegenerative and neurodevelopmental diseases.
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http://dx.doi.org/10.1016/j.bcp.2013.07.028DOI Listing
October 2013

NGF-induced cell differentiation and gene activation is mediated by integrative nuclear FGFR1 signaling (INFS).

PLoS One 2013 10;8(7):e68931. Epub 2013 Jul 10.

Department of Pathology and Anatomical Sciences, State University of New York at Buffalo, Buffalo, New York, United States of America.

Nerve growth factor (NGF) is the founding member of the polypeptide neurotrophin family responsible for neuronal differentiation. To determine whether the effects of NGF rely upon novel Integrative Nuclear FGF Receptor-1 (FGFR1) Signaling (INFS) we utilized the PC12 clonal cell line, a long-standing benchmark model of sympathetic neuronal differentiation. We demonstrate that NGF increases expression of the fgfr1 gene and promotes trafficking of FGFR1 protein from cytoplasm to nucleus by inhibiting FGFR1 nuclear export. Nuclear-targeted dominant negative FGFR1 antagonizes NGF-induced neurite outgrowth, doublecortin (dcx) expression and activation of the tyrosine hydroxylase (th) gene promoter, while active constitutive nuclear FGFR1 mimics the effects of NGF. NGF increases the expression of dcx, th, βIII tubulin, nurr1 and nur77, fgfr1and fibroblast growth factor-2 (fgf-2) genes, while enhancing binding of FGFR1and Nur77/Nurr1 to those genes. NGF activates transcription from isolated NurRE and NBRE motifs. Nuclear FGFR1 transduces NGF activation of the Nur dimer and raises basal activity of the Nur monomer. Cooperation of nuclear FGFR1 with Nur77/Nurr1 in NGF signaling expands the integrative functions of INFS to include NGF, the first discovered pluripotent neurotrophic factor.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0068931PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3707895PMC
March 2014

Medicinal Fungus Antrodia cinnamomea Inhibits Growth and Cancer Stem Cell Characteristics of Hepatocellular Carcinoma.

Evid Based Complement Alternat Med 2013 6;2013:569737. Epub 2013 Mar 6.

Cancer Center, Taipei Veterans General Hospital, Taipei 11217, Taiwan ; Institute of Traditional Medicine, School of Medicine, National Yang Ming University, Taipei 11221, Taiwan.

Background. Antrodia cinnamomea is an edible fungus commonly used in Asia as a well-known medicinal herb capable of treating drug intoxication and liver cancer. Methods. This study evaluated the anticancer activity of its biotechnological product, mycelial fermentation broth (AC-MFB) on hepatocellular carcinoma (HCC) by tetrazolium-based colorimetric assay in vitro and syngeneic Balb/c 1MEA.7R.1 tumor implantation model in vivo. Given that cancer stem cell characteristics, such as angiogenesis, invasiveness, and migration, are known to cause recurrence, we further evaluated the effect of AC-MFB on cellular viability inhibition of HCC cells, angiogenic activity and migration of endothelial cells, and the release of proangiogenic factors from HCC cells. Results. We found that AC-MFB markedly inhibited the growth of HCC without hepatic enzyme abnormality. This anti-HCC activity was validated by growth-inhibitory effects on both cultured murine 1MEA.7R.1 and human HA22T/VGH HCC cells. For cancer stem cell characteristics, AC-MFB inhibited the cellular viability, migration, and tube formation activity of EA. hy926 and SVEC4-10 endothelial cells. Production of extracellular vascular endothelial growth factor and intracellular hypoxia-inducible factor-1 alpha from HCC cells was suppressed by AC-MFB. Conclusion. Antrodia cinnamomea could inhibit the growth and cancer stem cell characteristics of HCC cells.
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http://dx.doi.org/10.1155/2013/569737DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3606723PMC
March 2013

A novel nuclear FGF Receptor-1 partnership with retinoid and Nur receptors during developmental gene programming of embryonic stem cells.

J Cell Biochem 2012 Sep;113(9):2920-36

Molecular and Structural Neurobiology and Gene Therapy Program, Department of Pathology and Anatomical Sciences, State University of New York, Buffalo, New York 14214, USA.

FGF Receptor-1 (FGFR1), a membrane-targeted protein, is also involved in independent direct nuclear signaling. We show that nuclear accumulation of FGFR1 is a common response to retinoic acid (RA) in pluripotent embryonic stem cells (ESC) and neural progenitors and is both necessary and sufficient for neuronal-like differentiation and accompanying neuritic outgrowth. Dominant negative nuclear FGFR1, which lacks the tyrosine kinase domain, prevents RA-induced differentiation while full-length nuclear FGFR1 elicits differentiation in the absence of RA. Immunoprecipitation and GST assays demonstrate that FGFR1 interacts with RXR, RAR and their Nur77 and Nurr1 partners. Conditions that promote these interactions decrease the mobility of nuclear FGFR1 and RXR in live cells. RXR and FGFR1 co-associate with 5'-Fluorouridine-labeled transcription sites and with RA Responsive Elements (RARE). RA activation of neuronal (tyrosine hydroxylase) and neurogenic (fgf-2 and fgfr1) genes is accompanied by increased FGFR1, Nur, and histone H3.3 binding to their regulatory sequences. Reporter-gene assays show synergistic activations of RARE, NBRE, and NurRE by FGFR1, RAR/RXR, and Nurs. As shown for mESC differentiation, FGFR1 mediates gene activation by RA and augments transcription in the absence of RA. Cooperation of FGFR1 with RXR/RAR and Nurs at targeted genomic sequences offers a new mechanism in developmental gene regulation.
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http://dx.doi.org/10.1002/jcb.24170DOI Listing
September 2012

Cooperation of nuclear fibroblast growth factor receptor 1 and Nurr1 offers new interactive mechanism in postmitotic development of mesencephalic dopaminergic neurons.

J Biol Chem 2012 Jun 18;287(24):19827-40. Epub 2012 Apr 18.

Institute of Neuroanatomy, Hannover Medical School, 30625 Hannover, Germany.

Experiments in mice deficient for Nurr1 or expressing the dominant-negative FGF receptor (FGFR) identified orphan nuclear receptor Nurr1 and FGFR1 as essential factors in development of mesencephalic dopaminergic (mDA) neurons. FGFR1 affects brain cell development by two distinct mechanisms. Activation of cell surface FGFR1 by secreted FGFs stimulates proliferation of neural progenitor cells, whereas direct integrative nuclear FGFR1 signaling (INFS) is associated with an exit from the cell cycle and neuronal differentiation. Both Nurr1 and INFS activate expression of neuronal genes, such as tyrosine hydroxylase (TH), which is the rate-limiting enzyme in dopamine synthesis. Here, we show that nuclear FGFR1 and Nurr1 are expressed in the nuclei of developing TH-positive cells in the embryonic ventral midbrain. Both nuclear receptors were effectively co-immunoprecipitated from the ventral midbrain of FGF-2-deficient embryonic mice, which previously showed an increase of mDA neurons and enhanced nuclear FGFR1 accumulation. Immunoprecipitation and co-localization experiments showed the presence of Nurr1 and FGFR1 in common nuclear protein complexes. Fluorescence recovery after photobleaching and chromatin immunoprecipitation experiments demonstrated the Nurr1-mediated shift of nuclear FGFR1-EGFP mobility toward a transcriptionally active population and that both Nurr1 and FGFR1 bind to a common region in the TH gene promoter. Furthermore, nuclear FGFR1 or its 23-kDa FGF-2 ligand (FGF-2(23)) enhances Nurr1-dependent activation of the TH gene promoter. Transcriptional cooperation of FGFR1 with Nurr1 was confirmed on isolated Nurr1-binding elements. The proposed INFS/Nurr1 nuclear partnership provides a novel mechanism for TH gene regulation in mDA neurons and a potential therapeutic target in neurodevelopmental and neurodegenerative disorders.
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http://dx.doi.org/10.1074/jbc.M112.347831DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3370168PMC
June 2012

Targeting novel integrative nuclear FGFR1 signaling by nanoparticle-mediated gene transfer stimulates neurogenesis in the adult brain.

Integr Biol (Camb) 2009 Jun 8;1(5-6):394-403. Epub 2009 May 8.

Molecular and Structural Neurobiology and Gene Therapy Program, Department of Pathology and Anatomical Sciences, State University of New York, Buffalo, NY 14214, USA.

Neurogenesis, the process of differentiation of neuronal stem/progenitor cells (NS/PC) into mature neurons, holds the key to the treatment of various neurodegenerative disorders, which are a major health issue for the world's aging population. We report that targeting the novel integrative nuclear FGF Receptor 1 signaling (INFS) pathway enhances the latent potential of NS/PCs to undergo neuronal differentiation, thus promoting neurogenesis in the adult brain. Employing organically modified silica (ORMOSIL)-DNA nanoplexes to efficiently transfect recombinant nuclear forms of FGFR1 and its FGF-2 ligand into the brain subventricular zone, we find that INFS stimulates the NS/PC to withdraw from the cell cycle, differentiate into doublecortin expressing migratory neuroblasts and neurons that migrate to the olfactory bulb, subcortical brain regions and in the brain cortex. Thus, nanoparticle-mediated non-viral gene transfer may be used to induce selective differentiation of NS/PCs, providing a potentially significant impact on the treatment of a broad range of neurological disorders.
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http://dx.doi.org/10.1039/b902617gDOI Listing
June 2009

Fibroblast growth factor receptor-1 (FGFR1) nuclear dynamics reveal a novel mechanism in transcription control.

Mol Biol Cell 2009 May 4;20(9):2401-12. Epub 2009 Mar 4.

Department of Pathology and Anatomical Sciences, and Department of Chemistry, State University of New York, Buffalo, NY 14214, USA.

Nuclear FGFR1 acts as a developmental gene regulator in cooperation with FGF-2, RSK1, and CREB-binding protein (CBP). FRAP analysis revealed three nuclear FGFR1 populations: i) a fast mobile, ii) a slower mobile population reflecting chromatin-bound FGFR1, and iii) an immobile FGFR1 population associated with the nuclear matrix. Factors (cAMP, CBP) that induce FGFR1-mediated gene activation shifted FGFR1 from the nuclear matrix (immobile) to chromatin (slow) and reduced the movement rate of the chromatin-bound population. Transcription inhibitors accelerated FGFR1 movement; the content of the chromatin-bound slow FGFR1 decreased, whereas the fast population increased. The transcriptional activation appears to involve conversion of the immobile matrix-bound and the fast nuclear FGFR1 into a slow chromatin-binding population through FGFR1's interaction with CBP, RSK1, and the high-molecular-weight form of FGF-2. Our findings support a general mechanism in which gene activation is governed by protein movement and collisions with other proteins and nuclear structures.
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http://dx.doi.org/10.1091/mbc.e08-06-0600DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2675620PMC
May 2009

Lysophospholipids increase ICAM-1 expression in HUVEC through a Gi- and NF-kappaB-dependent mechanism.

Am J Physiol Cell Physiol 2004 Dec 4;287(6):C1657-66. Epub 2004 Aug 4.

Department of Life Science and Institute of Zoology, National Taiwan University, Taipei, Taiwan 106, ROC.

Lysophosphatidic acid (LPA) and sphingosine 1-phosphate (S-1-P) are both low molecular weight lysophospholipid (LPL) ligands that are recognized by the Edg family of G protein-coupled receptors. In endothelial cells, these two ligands activate Edg receptors, resulting in cell proliferation and cell migration. The intercellular adhesion molecule-1 (ICAM-1, CD54) is one of many cell adhesion molecules belonging to the immunoglobulin superfamily. This study showed that LPA and S-1-P enhance ICAM-1 expression at both the mRNA and protein levels in human umbilical cord vein endothelial cells (HUVECs). This enhanced ICAM-1 expression in HUVECs was first observed at 2 h postligand treatment. Maximal expression appeared at 8 h postligand treatment, as detected by flow cytometry and Western blotting. Furthermore, the effects of S-1-P on ICAM-1 expression were shown to be concentration dependent. Prior treatment of HUVECs with pertussis toxin, a specific inhibitor of G(i), ammonium pyrrolidinedithiocarbamate and BAY 11-7082, inhibitors of the nuclear factor (NF)-kappaB pathway, or Clostridium difficile toxin B, an inhibitor of Rac, prevented the enhanced effect of LPL-induced ICAM-1 expression. However, pretreatment of HUVECs with exoC3, an inhibitor of Rho, had no effect on S-1-P-enhanced ICAM-1 expression. In a static cell-cell adhesion assay system, pretreatment of LPL enhanced the adhesion between HUVECs and U-937 cells, a human mononucleated cell line. The enhanced adhesion effect could be prevented by preincubation with a functional blocking antibody against human ICAM-1. These results suggest that LPLs released by activated platelets might enhance interactions of leukocytes with the endothelium through a G(i)-, NF-kappaB-, and possibly Rac-dependent mechanism, thus facilitating wound healing and inflammation processes.
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http://dx.doi.org/10.1152/ajpcell.00172.2004DOI Listing
December 2004